It is the long-range goal of this project to study the inactivation of prostaglandins by the lungs and other tissues. The effects of environmental agents on the pulmonary transport and metabolism of prostaglandins is being investigated, and these effects are being related to pulmonary toxicity and damage caused by the environmental agents. Topics of current interest are the structural requirements of a prostaglandin needed for transport to intracellular spaces, the effect of oxidant gases on transport, and the potentiation of inflammatory reaction by inhibition of pulmonary inactivation of prostaglandins.